C. Basu, H. Hirsh, and W. Cohen. AAAI '98/IAAI '98: Proceedings of the fifteenth national/tenth conference on Artificial intelligence/Innovative applications of artificial intelligence, page 714--720. Menlo Park, CA, USA, American Association for Artificial Intelligence, (1998)
P. Mika. The Semantic Web - ISWC 2005, Proceedings of the 4th International Semantic Web Conference, ISWC 2005, Galway, Ireland, November 6-10, volume 3729 of Lecture Notes in Computer Science, page 522-536. Heidelberg, Springer, (2005)